Method and apparatus for sending reference signal, and method and apparatus for obtaining reference signal

ABSTRACT

Embodiments of the present invention provide a method and an apparatus for sending a reference signal, and a method and an apparatus for obtaining a reference signal. The method for sending a reference signal includes: determining, based on a resource that is allocated to a reference signal in a basic pattern corresponding to the reference signal and a resource that is allocated to at least one basic pattern in a physical layer transmission unit, a resource occupied by the reference signal in the physical layer transmission unit; and sending the reference signal through the determined resource. It can be learned that, according to the technical solutions provided in the embodiments of the present invention, arrangement of the reference signal in the physical layer transmission unit can be flexibly set.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/401,826, filed on May 2, 2019, which is a continuation ofInternational Application No. PCT/CN2017/100415, filed on Sep. 4, 2017,which claims priority to Chinese Patent Application No. 201610953606.6,filed on Nov. 3, 2016 and Chinese Patent Application No. 201611027749.0,filed on Nov. 17, 2016. All of the aforementioned patent applicationsare hereby incorporated by reference in their entireties.

TECHNICAL FIELD

Embodiments of the present disclosure relate to wireless communicationstechnologies, and in particular, to a method and an apparatus forsending a reference signal, and a method and an apparatus for obtaininga reference signal.

BACKGROUND

A reference signal (RS) is also referred to as a pilot or a trainingsequence, and is known to a transmit end device and a receive enddevice. The reference signal has a plurality of purposes. Based onspecific purposes, the reference signal may be classified into aplurality of types, for example but not limited to, a reference signalused to obtain channel state information (CSI), a reference signal usedto demodulate a received signal, and a reference signal used for beammanagement. Particularly, some reference signals may have a plurality ofpurposes. A manner of transmitting the reference signal andconfiguration of a resource for carrying the reference signal may varyaccording to a purpose of the reference signal.

In the prior art, a reference signal is usually arranged according to afixed resource distribution pattern. FIG. 1 is a schematic diagram of anexample of a resource distribution pattern 100 of an existing referencesignal. As shown in FIG. 1, resource elements (RE) occupied by areference signal R corresponding to an antenna port are distributed intwo resource blocks 104 and 106 included in a resource block pair 102.In the resource block pair 102, the resource elements for carrying thereference signal have fixed locations.

Such a manner of arranging a reference signal according to a fixedresource distribution pattern is inflexible, and is problematic indifferent scenarios.

SUMMARY

In view of this, it is necessary to provide a method for sending areference signal, to flexibly arrange the reference signal.

In addition, a method for obtaining a reference signal is provided, toflexibly arrange the reference signal.

In addition, an apparatus for sending a reference signal is provided, toflexibly arrange the reference signal.

In addition, an apparatus for obtaining a reference signal is provided,to flexibly arrange the reference signal.

According to a first aspect of the embodiments of the presentdisclosure, a method for sending a reference signal is provided,including: determining, based on a resource that is allocated to areference signal in a basic pattern corresponding to the referencesignal and a resource that is allocated to at least one basic pattern ina physical layer transmission unit, a resource to be occupied by thereference signal in the physical layer transmission unit; and sendingthe reference signal through the determined resource.

In a possible design, the basic pattern occupies at least one OFDMsymbol in time domain, and occupies at least one subcarrier in frequencydomain. In addition, in a possible design, in the basic pattern, thereference signal occupies at least one OFDM symbol in time domain, andoccupies at least one subcarrier in frequency domain. Moreover, in apossible design, the at least one OFDM symbol occupied by the referencesignal in the basic pattern in time domain is a plurality of consecutiveOFDM symbols. In addition, in a possible design, the reference signal isused for at least one of the following objectives: determining channelstate information; performing beam management; and demodulating areceived signal.

Moreover, in a possible design, the basic pattern of the referencesignal is known to a transmit end device of the reference signal and areceive end device of the reference signal. In a specific implementationprocess, the basic pattern of the reference signal may be predefined ina design specification of a communications standard or a communicationssystem.

In addition, in a possible design, the method further includes a stepthat the transmit end device notifies the receive end device of theresource that is allocated to the at least one basic pattern in thephysical layer transmission unit. Further, the transmit end device maynotify, by using physical layer signaling, the receive end device of theresource that is allocated to the at least one basic pattern in thephysical layer transmission unit.

In a possible design, a quantity of reference signals corresponding to abasic pattern carried in the physical layer transmission unit, aquantity of basic patterns of each reference signal in the physicallayer transmission unit, and a resource occupied by the basic pattern inthe physical layer transmission unit may be set based on a specificrequirement. In addition, one physical layer transmission unit may carrya basic pattern of at least one reference signal. In addition, onephysical layer transmission unit may carry one or more basic patterns ofa same reference signal. Moreover, a resource occupied by each basicpattern of each reference signal in the physical layer transmission unitmay be set based on a specific requirement.

In a possible design, a quantity of OFDM symbols occupied by the basicpattern of the reference signal in time domain, a quantity ofsubcarriers occupied by the basic pattern of the reference signal infrequency domain, and a resource occupied by the reference signal in thebasic pattern of the reference signal may be set based on a specificrequirement. Further, the basic pattern of the reference signal mayoccupy at least one OFDM symbol in time domain, and may occupy at leastone subcarrier in frequency domain, the at least one OFDM symbol may beconsecutive, and the at least one subcarrier may also be consecutive. Inthe basic pattern of the reference signal, the reference signal mayoccupy at least one OFDM symbol in time domain, and may occupy at leastone subcarrier in frequency domain.

According to another aspect of the embodiments of the presentdisclosure, a method for obtaining a reference signal is provided,including: determining, based on a resource that is allocated to areference signal in a basic pattern corresponding to the referencesignal and a resource that is allocated to at least one basic pattern ina physical layer transmission unit, a resource occupied by the referencesignal in the physical layer transmission unit; and obtaining thereference signal through the determined resource.

In a possible design, the basic pattern occupies at least one OFDMsymbol in time domain, and occupies at least one subcarrier in frequencydomain. In addition, in a possible design, in the basic pattern, thereference signal occupies at least one OFDM symbol in time domain, andoccupies at least one subcarrier in frequency domain. Moreover, in apossible design, the at least one OFDM symbol occupied by the referencesignal in the basic pattern in time domain is a plurality of consecutiveOFDM symbols. In addition, in a possible design, the reference signal isused for at least one of the following objectives: determining channelstate information; performing beam management; and demodulating areceived signal.

Moreover, in a possible design, the basic pattern of the referencesignal is known to a transmit end device of the reference signal and areceive end device of the reference signal. In a specific implementationprocess, the basic pattern of the reference signal may be predefined ina design specification of a communications standard or a communicationssystem.

In addition, in a possible design, the method may further include a stepthat the receive end device obtains the resource that is allocated tothe at least one basic pattern in the physical layer transmission unit.Further, information carrying the resource that is allocated to the atleast one basic pattern in the physical layer transmission unit may besent from the transmit end device to the receive end device by usingphysical layer signaling.

In a possible design, a quantity of reference signals corresponding to abasic pattern carried in the physical layer transmission unit, aquantity of basic patterns of each reference signal in the physicallayer transmission unit, and a resource occupied by the basic pattern inthe physical layer transmission unit may be set based on a specificrequirement. In addition, one physical layer transmission unit may carrya basic pattern of at least one reference signal. In addition, onephysical layer transmission unit may carry one or more basic patterns ofa same reference signal. Moreover, a resource occupied by each basicpattern of each reference signal in the physical layer transmission unitmay be set based on a specific requirement.

In a possible design, a quantity of OFDM symbols occupied by the basicpattern of the reference signal in time domain, a quantity ofsubcarriers occupied by the basic pattern of the reference signal infrequency domain, and a resource occupied by the reference signal in thebasic pattern of the reference signal may be set based on a specificrequirement. Further, the basic pattern of the reference signal mayoccupy at least one OFDM symbol in time domain, and may occupy at leastone subcarrier in frequency domain, the at least one OFDM symbol may beconsecutive, and the at least one subcarrier may also be consecutive. Inthe basic pattern, the reference signal may occupy at least one OFDMsymbol in time domain, and may occupy at least one subcarrier infrequency domain.

According to still another aspect of the embodiments of the presentdisclosure, an apparatus for sending a reference signal is provided,including: a determining module, configured to determine, based on aresource that is allocated to a reference signal in a basic patterncorresponding to the reference signal and a resource that is allocatedto at least one basic pattern in a physical layer transmission unit, aresource to be occupied by the reference signal in the physical layertransmission unit; and a sending module, configured to send thereference signal through the determined resource.

In a possible design, the basic pattern occupies at least one OFDMsymbol in time domain, and occupies at least one subcarrier in frequencydomain. In addition, in a possible design, in the basic pattern, thereference signal occupies at least one OFDM symbol in time domain, andoccupies at least one subcarrier in frequency domain. Moreover, in apossible design, the at least one OFDM symbol occupied by the referencesignal in the basic pattern in time domain is a plurality of consecutiveOFDM symbols. In addition, in a possible design, the reference signal isused for at least one of the following objectives: determining channelstate information; performing beam management; and demodulating areceived signal.

Moreover, in a possible design, the basic pattern of the referencesignal is known to a transmit end device of the reference signal and areceive end device of the reference signal. In a specific implementationprocess, the basic pattern of the reference signal may be predefined ina design specification of a communications standard or a communicationssystem.

In addition, in a possible design, the sending module may be furtherconfigured to send, to the receive end device, information about theresource that is allocated to the at least one basic pattern in thephysical layer transmission unit. Further, the information may becarried in physical layer signaling.

In a possible design, a quantity of reference signals corresponding to abasic pattern carried in the physical layer transmission unit, aquantity of basic patterns of each reference signal in the physicallayer transmission unit, and a resource occupied by the basic patternsin the physical layer transmission unit may be set based on a specificrequirement. In addition, one physical layer transmission unit may carrya basic pattern of at least one reference signal. In addition, onephysical layer transmission unit may carry one or more basic patterns ofa same reference signal. Moreover, a resource occupied by each basicpattern of each reference signal in the physical layer transmission unitmay be set based on a specific requirement.

In a possible design, a quantity of OFDM symbols occupied by the basicpattern of the reference signal in time domain, a quantity ofsubcarriers occupied by the basic pattern of the reference signal infrequency domain, and a resource occupied by the reference signal in thebasic pattern of the reference signal may be set based on a specificrequirement. Further, the basic pattern of the reference signal mayoccupy at least one OFDM symbol in time domain, and may occupy at leastone subcarrier in frequency domain, the at least one OFDM symbol may beconsecutive, and the at least one subcarrier may also be consecutive. Inthe basic pattern, the reference signal may occupy at least one OFDMsymbol in time domain, and may occupy at least one subcarrier infrequency domain.

According to yet another aspect of the embodiments of the presentdisclosure, an apparatus for obtaining a reference signal is provided,including: a determining module, configured to determine, based on aresource that is allocated to a reference signal in a basic patterncorresponding to the reference signal and a resource that is allocatedto at least one basic pattern in a physical layer transmission unit, aresource occupied by the reference signal in the physical layertransmission unit; and an obtaining module, configured to obtain thereference signal through the determined resource.

In a possible design, the basic pattern occupies at least one OFDMsymbol in time domain, and occupies at least one subcarrier in frequencydomain. In addition, in a possible design, in the basic pattern, thereference signal occupies at least one OFDM symbol in time domain, andoccupies at least one subcarrier in frequency domain. Moreover, in apossible design, the at least one OFDM symbol occupied by the referencesignal in the basic pattern in time domain is a plurality of consecutiveOFDM symbols. In addition, in a possible design, the reference signal isused for at least one of the following objectives: determining channelstate information; performing beam management; and demodulating areceived signal.

Moreover, in a possible design, the basic pattern of the referencesignal is known to a transmit end device of the reference signal and areceive end device of the reference signal. In a specific implementationprocess, the basic pattern of the reference signal may be predefined ina design specification of a communications standard or a communicationssystem.

In addition, in a possible design, the determining module may be furtherconfigured to obtain information about the resource that is allocated tothe at least one basic pattern in the physical layer transmission unit.Further, the information may be carried in physical layer signaling.

In a possible design, a quantity of reference signals corresponding to abasic pattern carried in the physical layer transmission unit, aquantity of basic patterns of each reference signal in the physicallayer transmission unit, and a resource occupied by the basic pattern inthe physical layer transmission unit may be set based on a specificrequirement. In addition, one physical layer transmission unit may carrya basic pattern of at least one reference signal. In addition, onephysical layer transmission unit may carry one or more basic patterns ofa same reference signal. Moreover, a resource occupied by each basicpattern of each reference signal in the physical layer transmission unitmay be set based on a specific requirement.

In a possible design, a quantity of OFDM symbols occupied by the basicpattern of the reference signal in time domain, a quantity ofsubcarriers occupied by the basic pattern of the reference signal infrequency domain, and a resource occupied by the reference signal in thebasic pattern of the reference signal may be set based on a specificrequirement. Further, the basic pattern of the reference signal mayoccupy at least one OFDM symbol in time domain, and may occupy at leastone subcarrier in frequency domain, the at least one OFDM symbol may beconsecutive, and the at least one subcarrier may also be consecutive. Inthe basic pattern, the reference signal may occupy at least one OFDMsymbol in time domain, and may occupy at least one subcarrier infrequency domain.

According to the technical solutions provided in the embodiments of thepresent disclosure, arrangement of the reference signal carried in thebasic pattern in the physical layer transmission unit can be set byadjusting a quantity of basic patterns carried in the physical layertransmission unit and a location of a resource occupied by each basicpattern in the physical layer transmission unit. It can be learned that,according to the technical solutions provided in the embodiments of thepresent disclosure, compared with a fixed reference signal arrangementmanner in the prior art, arrangement of the reference signal in thephysical layer transmission unit can be flexibly set.

In addition, according to the technical solutions provided in theembodiments of the present disclosure, based on a specific requirement,for example but not limited to, received signal quality of the receiveend device, a channel state, a moving speed, a quantity of data streamsfor which spatial multiplexing is performed, a processing capability, aquantity of simultaneously scheduled receive end devices, a relateddesign parameter of beam management, or system bandwidth, the transmitend device adjusts the quantity of basic patterns carried in thephysical layer transmission unit and the location of the resourceoccupied by each basic pattern in the physical layer transmission unit,to flexibly adjust arrangement of the reference signal carried in thebasic pattern in the physical layer transmission unit.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic diagram of an example of a resource distributionpattern of an existing reference signal;

FIG. 2 is a schematic diagram of an example of a wireless communicationsnetwork according to an embodiment of the present disclosure;

FIG. 3 is an example flowchart of a method for sending a referencesignal according to an embodiment of the present disclosure;

FIG. 4 is a schematic diagram of a logical structure of a physical layertransmission unit according to an embodiment of the present disclosure;

FIG. 4A is a schematic diagram of a logical structure of a physicallayer transmission unit according to another embodiment of the presentdisclosure;

FIG. 5 is an example flowchart of a method for obtaining a referencesignal according to an embodiment of the present disclosure;

FIG. 6 is a schematic diagram of a logical structure of an apparatus forsending a reference signal according to an embodiment of the presentdisclosure;

FIG. 7 is a schematic diagram of a logical structure of an apparatus forobtaining a reference signal according to an embodiment of the presentdisclosure;

FIG. 8 is a schematic diagram of a hardware structure of an apparatusfor sending a reference signal according to an embodiment of the presentdisclosure; and

FIG. 9 is a schematic diagram of a hardware structure of an apparatusfor obtaining a reference signal according to an embodiment of thepresent disclosure.

DESCRIPTION OF EMBODIMENTS

In technical solutions provided in the embodiments of the presentdisclosure, a corresponding basic pattern is set for a reference signal,and a plurality of different arrangement manners of the reference signalin a physical layer transmission unit can be designed by adjusting aresource occupied by at least one basic pattern in the physical layertransmission unit, to meet different requirements on the referencesignal in different scenarios. It can be learned that, according to thetechnical solutions provided in the embodiments of the presentdisclosure, arrangement of the reference signal in the physical layertransmission unit can be flexibly set. The following describes thetechnical solutions provided in the embodiments of the presentdisclosure in detail with reference to corresponding accompanyingdrawings.

FIG. 2 is a schematic diagram of an example of a wireless communicationsnetwork 200 according to an embodiment of the present disclosure. Asshown in FIG. 2, the wireless communications network 200 includes basestations 202 to 206 and terminal devices 208 to 222. The base stations202 to 206 may communicate with each other over backhaul (backhaul)links (shown by straight lines between the base stations 202 to 206).The backhaul link may be a wired backhaul link (for example, an opticalfiber or a copper cable), or may be a wireless backhaul link (forexample, microwave). The terminal devices 208 to 222 may communicatewith the corresponding base stations 202 to 206 over radio links (shownby polygonal lines between the base stations 202 to 206 and the terminaldevices 208 to 222).

The base stations 202 to 206 are configured to provide a wireless accessservice for the terminal devices 208 to 222. Specifically, each basestation corresponds to a service coverage area (which may also bereferred to as a cell, and is shown by each elliptical area in FIG. 2).A terminal device that enters the area may communicate with the basestation by using a radio signal, to accept the wireless access serviceprovided by the base station. Service coverage areas of base stationsmay overlap, and a terminal device in an overlapping area may receiveradio signals from a plurality of base stations. Therefore, theplurality of base stations may serve the terminal device. For example,the plurality of base stations may serve the terminal device in theoverlapping area by using a coordinated multipoint (CoMP) technology.For example, as shown in FIG. 2, an overlapping area exists betweenservice coverage areas of the base station 202 and the base station 204,and the terminal device 212 is in the overlapping area. Therefore, theterminal device 212 may receive radio signals from the base station 202and the base station 204, and both the base station 202 and the basestation 204 may serve the terminal device 212. For another example, asshown in FIG. 2, a common overlapping area exists among service coverageareas of the base station 202, the base station 204, and the basestation 206, and the terminal device 220 is in the overlapping area.Therefore, the terminal device 220 may receive radio signals from thebase station 202, the base station 204, and the base station 206, andthe base station 202, the base station 204, and the base station 206 mayall serve the terminal device 220.

Depending on a used wireless communications technology, the base stationmay also be referred to as a NodeB, an evolved NodeB (eNodeB), an accesspoint (AP), or the like. In addition, based on sizes of coverage areasof provided services, the base stations may be classified as a macrobase station configured to provide a macro cell, a micro base stationconfigured to provide a micro cell (Pico cell), or a femto base stationconfigured to provide a femto cell. With continuous evolution ofwireless communications technologies, a future base station may haveanother name.

The terminal devices 208 to 222 may be various wireless communicationsdevices having a wireless communication function, for example but notlimited to, a mobile cellular phone, a cordless telephone set, apersonal digital assistant (PDA), a smartphone, a notebook computer, atablet computer, a wireless data card, a wireless modem(Modulator-demodulator, Modem), and a wearable device such as asmartwatch. With rise of the Internet of Things (IoT) technology, anincreasing quantity of devices that previously do not have acommunication function, for example but not limited to, householdappliances, vehicles, tools, service devices, and service facilities,begin to obtain the wireless communication function with a wirelesscommunications unit configured, so that the devices can access awireless communications network and be remotely controlled. Such deviceshave the wireless communication function because they are configuredwith the wireless communications unit, and therefore also fall within ascope of wireless communications devices. In addition, the terminaldevices 208 to 222 each may also be referred to as a mobile station, amobile device, a mobile terminal, a wireless terminal, a handhelddevice, a client, or the like.

The base stations 202 to 206 and the terminal devices 208 to 222 may allhave a plurality of antennas configured, to support a MIMO (MultipleInput Multiple Output) technology. Further, the terminal devices 208 to222 may support a single-user MIMO (SU-MIMO) technology, and may alsosupport multi-user MIMO (MU-MIMO). The MU-MIMO may be implemented basedon a space division multiple access (SDMA) technology. Because of theplurality of configured antennas, the base stations 202 to 206 and theterminal devices 208 to 222 may further flexibly support a single inputsingle output (SISO) technology, a single input multiple output (SIMO)technology, and a multiple input single output (MISO) technology, toimplement various diversity (for example but not limited to, transmitdiversity and receive diversity) and multiplexing technologies. Thediversity technology may include, for example but not limited to, atransmit diversity (TD) technology and a receive diversity (RD)technology. The multiplexing technology may be a spatial multiplexingtechnology. Moreover, the foregoing technologies may further include aplurality of implementation solutions. For example, current commontransmit diversity may include diversity manners, for example but notlimited to, space-time transmit diversity (STTD), space-frequencytransmit diversity (SFTD), time switched transmit diversity (TSTD),frequency switched transmit diversity (FSTD), orthogonal transmitdiversity (OTD), and cyclic delay diversity (CDD), and diversity mannersobtained after derivation, evolution, and combination of the foregoingdiversity manners. For example, in a current LTE (Long Term Evolution)standard, transmit diversity manners such as space time block coding(STBC), space frequency block coding (SFBC), and the CDD are used.

Moreover, the base station 202 to 206 may communicate with the terminaldevices 204 to 222 by using various wireless communicationstechnologies, for example but not limited to, a Time Division MultipleAccess (TDMA) technology, a Frequency Division Multiple Access (FDMA)technology, a Code Division Multiple Access (CDMA) technology, a TimeDivision-Synchronous Code Division Multiple Access (TD-SCDMA)technology, an orthogonal frequency division multiple access (OrthogonalFDMA, OFDMA) technology, a single carrier frequency division multipleaccess (Single Carrier FDMA, SC-FDMA) technology, a space divisionmultiple access (SDMA) technology, and technologies evolved and derivedfrom these technologies. The foregoing wireless communicationstechnologies are adopted as a radio access technology (RAT) in numerouswireless communications standards, to construct various wirelesscommunications systems (or networks) nowadays widely known to people,including but not limited to, a Global System for Mobile Communications(GSM) system, a CDMA2000, a Wideband CDMA (WCDMA), Wi-Fi defined in the802.11 series standard, Worldwide Interoperability for Microwave Access(WiMAX), Long Term Evolution (LTE), LTE-Advanced (LTE-A), and systemsevolved from these wireless communications systems. The wirelesscommunications network shown in FIG. 2 may be any system or network inthe foregoing wireless communications systems. Unless otherwise stated,the technical solutions provided in the embodiments of the presentdisclosure may be applied to the foregoing wireless communicationstechnologies and wireless communications systems. In addition, the terms“system” and “network” can be interchanged with each other.

It should be noted that, the wireless communications network 200 shownin FIG. 2 is merely an example, and is not intended to limit thetechnical solutions of the present disclosure. A person skilled in theart should understand that, in a specific implementation process, thewireless communications network 200 further includes another device, forexample but not limited to, a base station controller (BSC), andquantities of the base stations and the terminal devices may beconfigured based on a specific requirement.

FIG. 3 is an example flowchart of a method 300 for sending a referencesignal according to an embodiment of the present disclosure. In aspecific implementation process, the method 300 may be performed by atransmit end device. The transmit end device may be, for example but notlimited to, the base stations 202 to 206 or the terminal devices 208 to222 in FIG. 2.

Step 302: Determine, based on a resource that is allocated to areference signal in a basic pattern corresponding to the referencesignal and a resource that is allocated to at least one basic pattern ina physical layer transmission unit, a resource to be occupied by thereference signal in the physical layer transmission unit.

Step 304: Send the reference signal through the determined resource.

In the method 300, the basic pattern may occupy at least one OFDM symbolin time domain, and may occupy at least one subcarrier in frequencydomain. In addition, in the basic pattern, the reference signal mayoccupy at least one OFDM symbol in time domain, and may occupy at leastone subcarrier in frequency domain. In other words, the resource that isallocated to the reference signal in the basic pattern corresponding tothe reference signal may include at least one OFDM symbol in timedomain, and may include at least one subcarrier in frequency domain.More specifically, the at least one OFDM symbol occupied by thereference signal in the basic pattern in time domain may be a pluralityof consecutive OFDM symbols.

It should be noted that, in a specific implementation process, the OFDMsymbol may be replaced with a time unit or a time domain resource inanother form, and the subcarrier may be replaced with a frequency unitor a frequency domain resource in another form.

The reference signal is used for at least one of the followingobjectives:

determining channel state information;

performing beam management; and

demodulating a received signal.

A typical example of a reference signal used to determine channel stateinformation is a channel state information reference signal (CSI-RS)used in an LTE standard. A typical process of determining the CSI basedon the CSI-RS is: A base station transmits the CSI-RS, and the CSI-RS isreceived by a terminal device through propagation on a channel. Theterminal device compares the received CSI-RS with the CSI-RS transmittedby the base station (the CSI-RS transmitted by the base station is knownto the terminal device), to perform channel estimation and obtainchannel information, such as a channel matrix. Based on the channelinformation, a codebook, and other information, the terminal device mayfurther determine the channel state information, including, for examplebut not limited to, a precoding matrix indicator (PMI), a channelquality indicator (CQI), and a rank indication (RI).

A typical example of a reference signal used to demodulate a receivedsignal is a demodulation reference signal (DMRS) used in the LTEstandard. Because the DMRS and data are precoded by using a sameprecoding matrix, channel estimation may be performed on a precodedchannel (also referred to as an equivalent channel) based on the DMRS,and the data may be demodulated based on a result of the channelestimation.

In a 5G wireless communications system currently in a design stage, datais transmitted by using a high-frequency radio signal. Thehigh-frequency radio signal fades relatively fast. Therefore, abeamforming technology, for example but not limited to, digitalbeamforming, analog beamforming, or hybrid beamforming, needs to be usedto improve received signal quality. In a process of transmitting databased on a beam, a reference signal needs to be used in many processes,for example but not limited to, beam sweeping, beam selection, and beamtracking. The reference signal used during implementation of theprocesses may be referred to as a reference signal used for beammanagement. A related function of the reference signal is clearlydescribed in the prior art, for example but not limited to, a proposalsubmitted by a vendor in the industry at a standard organizationmeeting. Details are not described herein.

In a specific implementation process, a same type of reference signalmay have a plurality of different purposes. A typical example of thistype of reference signal is a cell-specific reference signal (CRS) usedin the LTE standard. The CRS is a common reference signal, and all userequipment in a cell may use a CRS of the cell. The CRS can be used toobtain channel state information, and can also be used to demodulate areceived signal. Similarly, a reference signal is described in the priorart, for example but not limited to, in a proposal submitted by a vendorin the industry at a standard organization meeting. The reference signalcan be used to determine channel state information, and can also be usedfor beam management. For specific details of the reference signal, referto the related proposal. Details are not described herein.

It should be noted that, the foregoing described specific examples ofreference signals and objectives of specific processes are intended touse examples to describe principles of the functions of the referencesignals and the specific processes of implementing the functions, butare not intended to limit the protection scope of the presentdisclosure. Actually, a person skilled in the art should understandthat, in addition to the specific examples and specific processesdescribed above, a reference signal having a corresponding function mayalternatively be another existing or redesigned reference signal, and acorresponding process may alternatively be another existing orredesigned process. Therefore, the protection scope of the embodimentsof the present disclosure should be understood as including allreference signals having the functions and all processes of implementingthe functions.

In addition, a person skilled in the art should understand that inaddition to the foregoing objectives, the reference signal in thetechnical solution provided in this embodiment of the present disclosuremay be a reference signal used for another objective.

Different basic patterns may be designed for different referencesignals. Different basic patterns may include different resources, and aresource occupied by one reference signal in a basic pattern of thereference signal may be different from a resource occupied by anotherreference signal in a basic pattern of the another reference signal. Itshould be noted that, different reference signals may be referencesignals used for different objectives, or may be reference signals usedfor a same objective. For simplicity, different reference signals may beunderstood as reference signals corresponding to different antennaports. In addition, a same basic pattern may correspond to a pluralityof reference signals, and these reference signals may share, in a mannersuch as time division multiplexing, frequency division multiplexing, orcode division multiplexing, a resource included in the basic pattern. Inaddition, a basic pattern of a reference signal should be known to atransmit end device of the reference signal and a receive end device ofthe reference signal. In a specific implementation process, the basicpattern of the reference signal may be predefined in a designspecification of a communications standard or a communications system.In this case, in a process of manufacturing the transmit end device andthe receive end device, the basic pattern of the reference signal may beprestored in the devices, or in a process of deploying the devices, thebasic pattern of the reference signal may be configured for the devices,or in a communications network access process of the devices, the basicpattern of the reference signal may be dynamically configured by usingvarious communication messages. For related technical solutions thatvarious communication parameters are configured for the transmit enddevice and the receive end device, refer to the prior art. Details arenot described herein.

The physical layer transmission unit may be, for example but not limitedto, a physical layer frame, a slot, a resource element, or a combinationof a plurality of resource elements. For a quantity of time-frequencyresources included in the transmission unit, refer to a provision in theexisting LTE standard. For example, for the physical layer frame, referto a subframe or a frame in the LTE standard; for the slot, refer to aslot in the LTE standard; for the resource element, refer to a resourceblock in the LTE standard; and for a combination of the plurality ofresource elements, refer to a resource block pair or a resource blockgroup in the LTE standard. In addition, the physical layer transmissionunit may be adjusted based on the foregoing unit described in theexisting LTE standard, or may be reset based on a requirement of asystem design.

In a specific implementation process, the basic pattern may be expressedin a plurality of forms such as a formula or a lookup table. For aspecific expression form of the basic pattern, refer to the prior art.Details are not described herein.

In a specific implementation process, in step 304, the transmit enddevice sends the reference signal to the receive end device through thedetermined resource. To enable the receive end device to learn theresource that is allocated to the at least one basic pattern in thephysical layer transmission unit, the method 300 may further include astep that the transmit end device notifies the receive end device of theresource that is allocated to the at least one basic pattern in thephysical layer transmission unit. In a specific implementation process,the transmit end device may notify the information by using varioustypes of signaling, for example but not limited to, physical layersignaling, media access control (MAC) layer signaling, and radioresource control (RRC) signaling. The information may carry, for examplebut not limited to, an index of a basic pattern, a quantity of basicpatterns, and a location of a time-frequency resource occupied by eachbasic pattern in the physical layer transmission unit.

The physical layer signaling may also be referred to as Layer 1 (L1)signaling, and may usually be carried by a control portion of thephysical layer transmission unit (for example, a physical layer frame).Atypical example of the L1 signaling is downlink control information(DCI) carried in a physical downlink control channel (PDCCH) defined inan LTE standard. In some cases, the L1 signaling may alternatively becarried by a data portion of the physical layer frame. It can be easilylearned that, a transmission period or a signaling period of the L1signaling is usually a period of the physical layer frame. Therefore,the signaling is usually used to implement some dynamic control.

The media access control layer signaling belongs to Layer 2 signaling,and may usually be carried by, for example but not limited to, a frameheader of a Layer 2 frame. The frame header may further carryinformation, for example but not limited to, information such as asource address and a destination address. In addition to the frameheader, the Layer 2 frame usually further includes a frame body. In somecases, the L2 signaling may alternatively be carried by the frame bodyof the Layer 2 frame. A typical example of the Layer 2 signaling issignaling carried in a frame control field in a frame header of a MACframe in the 802.11 series standard, or a MAC control entity defined insome protocols. The Layer 2 frame may usually be carried in a dataportion in a physical layer frame. Alternatively, the foregoinginformation may be sent by using another type of Layer 2 signaling otherthan the media access control layer signaling.

The radio resource control signaling belongs to Layer 3 signaling, andis usually some control messages. The L3 signaling may usually becarried in a frame body of a Layer 2 frame. The L3 signaling usually hasa relatively long transmission period or control period, and is suitablefor sending some information that does not frequently change. Forexample, in some existing communications standards, the L3 signaling isusually used to carry some configuration information. Alternatively, theforegoing information may be sent by using another type of Layer 3signaling other than the RRC signaling.

The foregoing is merely principle description of the physical layersignaling, the MAC layer signaling, the RRC signaling, the Layer 1signaling, the Layer 2 signaling, and the Layer 3 signaling. Forspecific details about the three types of signaling, refer to the priorart. Details are not described herein in this specification.

In addition, in a specific implementation process, the informationtransferred through the signaling may specifically include a quantity ofbasic patterns of a reference signal in the physical layer transmissionunit and a resource occupied by each basic pattern.

It can be easily learned that, arrangement of the reference signalcarried in the basic pattern in the physical layer transmission unit canbe set by adjusting a quantity of basic patterns carried in the physicallayer transmission unit and a location of a resource occupied by eachbasic pattern in the physical layer transmission unit. It can be learnedthat, according to the technical solution provided in this embodiment ofthe present disclosure, compared with a fixed reference signalarrangement manner in the prior art, arrangement of the reference signalin the physical layer transmission unit can be flexibly set. Therefore,according to the technical solution provided in this embodiment of thepresent disclosure, based on a specific requirement, for example but notlimited to, received signal quality of the receive end device, a channelstate, a moving speed, a quantity of data streams for which spatialmultiplexing is performed, a processing capability, a quantity ofsimultaneously scheduled receive end devices, a related design parameterof beam management, or system bandwidth, the transmit end device adjuststhe quantity of basic patterns carried in the physical layertransmission unit and the location of the resource occupied by eachbasic pattern in the physical layer transmission unit, to flexiblyadjust arrangement of the reference signal carried in the basic patternin the physical layer transmission unit.

The basic pattern provided in this embodiment of the present disclosureis described below with reference to FIG. 4.

FIG. 4 is a schematic diagram of a logical structure of a physical layertransmission unit 400 according to an embodiment of the presentdisclosure. As shown in FIG. 4, the physical layer transmission unit 400carries basic patterns corresponding to four reference signals: a basicpattern 402 corresponding to a reference signal R1, a basic pattern 404corresponding to a reference signal R2, a basic pattern 406corresponding to a reference signal R3, and a basic pattern 408corresponding to a reference signal R4. In addition, the referencesignal R1 corresponds to an antenna port 1, the reference signal R2corresponds to an antenna port 2, the reference signal R3 corresponds toan antenna port 3, and the reference signal R4 corresponds to an antennaport 4. Therefore, the basic pattern 402 may also be referred to as abasic pattern corresponding to the antenna port 1, the basic pattern 404may also be referred to as a basic pattern corresponding to the antennaport 2, the basic pattern 406 may also be referred to as a basic patterncorresponding to the antenna port 3, and the basic pattern 408 may alsobe referred to as a basic pattern corresponding to the antenna port 4.Actually, the antenna port and the reference signal are usually in aone-to-one correspondence, and can refer to each other. Therefore, theantenna port and the reference signal can be used interchangeably. Forexample, in the existing LTE standard, reference signals such as aCSI-RS, a CRS, and a DMRS separately correspond to different antennaports, and these reference signals and these antenna ports can usuallyrefer to each other or replace each other. A relationship between anantenna port and a reference signal is clearly described in the priorart. Therefore, details are not described herein.

Moreover, for the reference signal R1, the physical layer transmissionunit 400 carries two basic patterns of the reference signal; for thereference signal R2, the physical layer transmission unit 400 carriesone basic pattern of the reference signal; for the reference signal R3,the physical layer transmission unit 400 carries two basic patterns ofthe reference signal; and for the reference signal R4, the physicallayer transmission unit 400 carries one basic pattern of the referencesignal. In the physical layer transmission unit 400, the two basicpatterns 402 of the reference signal R1 are non-consecutive in timedomain. In other words, OFDM symbols on which the two basic patterns 402are located are non-consecutive in time domain. In addition, in thephysical layer transmission unit 400, the two basic patterns 406 of thereference signal R3 are consecutive in frequency domain. In other words,subcarriers on which the two basic patterns 406 are located areconsecutive in frequency domain.

It should be noted that, a person skilled in the art should understandthat, the physical layer transmission unit 400 shown in FIG. 4 is merelyintended to use an example to describe a manner of carrying a basicpattern of a reference signal in a physical layer transmission unit, andis not intended to limit the protection scope of this embodiment of thepresent disclosure. In a specific implementation process, a quantity ofreference signals corresponding to a basic pattern carried in thephysical layer transmission unit, a quantity of basic patterns of eachreference signal in the physical layer transmission unit, and a resourceoccupied by the basic pattern in the physical layer transmission unitmay be set based on a specific requirement. Actually, according to thetechnical solution provided in this embodiment of the presentdisclosure, one physical layer transmission unit may carry a basicpattern of at least one reference signal. In addition, one physicallayer transmission unit may carry one or more basic patterns of a samereference signal. Moreover, a resource occupied by each basic pattern ofeach reference signal in the physical layer transmission unit may be setbased on a specific requirement. In other words, a location of eachbasic pattern of each reference signal in the physical layertransmission unit may be set based on a specific requirement. Forexample, in the physical layer transmission unit 400, the two basicpatterns 402 of the reference signal R1 may be consecutively arranged intime domain. In addition, the two basic patterns 406 of the referencesignal R3 may be non-consecutively arranged in frequency domain.

As shown in FIG. 4, the basic pattern 402 of the reference signal R1occupies one OFDM symbol in time domain, and occupies a plurality ofconsecutive subcarriers in frequency domain; the basic pattern 404 ofthe reference signal R2 occupies two consecutive OFDM symbols in timedomain, and occupies a plurality of consecutive subcarriers in frequencydomain; the basic pattern 406 of the reference signal R3 occupies aplurality of consecutive OFDM symbols in time domain, and occupies onesubcarrier in frequency domain; and the basic pattern 408 of thereference signal R4 occupies a plurality of consecutive OFDM symbols intime domain, and occupies three consecutive subcarriers in frequencydomain.

It should be noted that, a person skilled in the art should understandthat, the basic patterns of the reference signals shown in FIG. 4 aremerely intended to use an example to describe a resource occupied by abasic pattern of a reference signal, and are not intended to limit theprotection scope of this embodiment of the present disclosure. In aspecific implementation process, a quantity of OFDM symbols occupied bythe basic pattern of the reference signal in time domain, a quantity ofsubcarriers occupied by the basic pattern of the reference signal infrequency domain, and a resource occupied by the reference signal in thebasic pattern of the reference signal may be set based on a specificrequirement. Actually, according to the technical solution provided inthis embodiment of the present disclosure, the basic pattern of thereference signal may occupy at least one OFDM symbol in time domain, andmay occupy at least one subcarrier in frequency domain, the at least oneOFDM symbol may be consecutive, and the at least one subcarrier may alsobe consecutive. In the basic pattern, the reference signal may occupy atleast one OFDM symbol in time domain, and may occupy at least onesubcarrier in frequency domain. For simplicity, the basic pattern of thereference signal may be set based on a specific requirement. Forexample, the quantity of OFDM symbols occupied by the basic pattern ofthe reference signal in time domain, the quantity of subcarriersoccupied by the basic pattern of the reference signal in frequencydomain, and the resource occupied by the reference signal in the basicpattern of the reference signal may be all set based on a specificrequirement.

FIG. 4A is a schematic diagram of a logical structure of a physicallayer transmission unit 400′ according to another embodiment of thepresent disclosure. As shown in FIG. 4A, the physical layer transmissionunit 400′ carries a basic pattern 402′, the basic pattern 402′ carriesreference signals R5, R6, R7, and R8, and the basic pattern correspondsto the reference signals R5, R6, R7, and R8. The reference signal R5corresponds to an antenna port 5, the reference signal R6 corresponds toan antenna port 6, the reference signal R7 corresponds to an antennaport 7, and the reference signal R8 corresponds to an antenna port 8.

As shown in FIG. 4A, in the basic pattern 402′, the reference signalsR5, R6, R7, and R8 occupy different time-frequency resources, forexample, occupy different resource elements. However, a person skilledin the art should understand that, in a specific implementation process,different reference signals may occupy a same time-frequency resourcethrough manners, for example but not limited to, code divisionmultiplexing.

It should be noted that, a person skilled in the art should understandthat, the physical layer transmission unit 400′ shown in FIG. 4A ismerely intended to use an example to describe a manner of carrying abasic pattern in a physical layer transmission unit, and is not intendedto limit the protection scope of this embodiment of the presentdisclosure. In a specific implementation process, a quantity of basicpatterns in the physical layer transmission unit and a resource occupiedby the basic pattern in the physical layer transmission unit may be setbased on a specific requirement. Actually, according to the technicalsolution provided in this embodiment of the present disclosure, onephysical layer transmission unit may carry at least one basic pattern.In addition, a resource occupied by the basic pattern in the physicallayer transmission unit may be set based on a specific requirement.

As shown in FIG. 4A, in the basic pattern 402′, the reference signal R5occupies four consecutive OFDM symbols in time domain, and occupies onesubcarrier in frequency domain; the reference signal R6 occupies twonon-consecutive OFDM symbols in time domain, and occupies one subcarrierin frequency domain; the reference signal R7 occupies one OFDM symbol intime domain, and occupies two non-consecutive subcarriers in frequencydomain; and the reference signal R8 occupies one OFDM symbol in timedomain, and occupies two consecutive subcarriers in frequency domain.

It should be noted that, a person skilled in the art should understandthat, the basic pattern 402′ shown in FIG. 4A is merely intended to usean example to describe a resource occupied by a basic pattern and aresource occupied by each reference signal in the basic pattern, and isnot intended to limit the protection scope of this embodiment of thepresent disclosure. In a specific implementation process, a quantity ofOFDM symbols occupied by the basic pattern in time domain, a quantity ofsubcarriers occupied by the basic pattern in frequency domain, and theresource occupied by each reference signal in the basic pattern may beset based on a specific requirement. Actually, according to thetechnical solution provided in this embodiment of the presentdisclosure, the basic pattern may occupy at least one OFDM symbol intime domain, and may occupy at least one subcarrier in frequency domain,the at least one OFDM symbol may be consecutive, and the at least onesubcarrier may also be consecutive. In the basic pattern, each referencesignal may occupy at least one OFDM symbol in time domain, and occupy atleast one subcarrier in frequency domain, and the occupied OFDM symboland subcarrier may be consecutive, or may be non-consecutive. Forsimplicity, the basic pattern may be set based on a specificrequirement. For example, the quantity of OFDM symbols occupied by thebasic pattern in time domain, the quantity of subcarriers occupied bythe basic pattern in frequency domain, and the resource occupied by eachreference signal in the basic pattern may be all set based on a specificrequirement.

FIG. 5 is a schematic flowchart of a method 500 for obtaining areference signal according to an embodiment of the present disclosure.In a specific implementation process, the method 500 may be performed bya receive end device. The receive end device may be, for example but notlimited to, the terminal devices 208 to 222 or the base stations 202 to206 in FIG. 2.

Step 502: Determine, based on a resource that is allocated to thereference signal in a basic pattern corresponding to a reference signaland a resource that is allocated to at least one basic pattern in aphysical layer transmission unit, a resource occupied by the referencesignal in the physical layer transmission unit.

Step 504: Obtain the reference signal through the determined resource.

In the method 500, the basic pattern may occupy at least one OFDM symbolin time domain, and may occupy at least one subcarrier in frequencydomain. In addition, in the basic pattern, the reference signal mayoccupy at least one OFDM symbol in time domain, and may occupy at leastone subcarrier in frequency domain. In other words, the resource that isallocated to the reference signal in the basic pattern corresponding tothe reference signal may include at least one OFDM symbol in timedomain, and may include at least one subcarrier in frequency domain.More specifically, the at least one OFDM symbol occupied by thereference signal in the basic pattern in time domain may be a pluralityof consecutive OFDM symbols.

The reference signal is used for at least one of the followingobjectives:

determining channel state information;

performing beam management; and

demodulating a received signal.

In a specific implementation process, to enable the receive end deviceto learn the resource that is allocated to the at least one basicpattern in the physical layer transmission unit, a transmit end devicemay also notify the receive end device of the resource that is allocatedto the at least one basic pattern in the physical layer transmissionunit. Therefore, the method 500 may further include a step that thereceive end device obtains the resource that is allocated to the atleast one basic pattern in the physical layer transmission unit. Relatedtechnical details that the transmit end device notifies the receive enddevice of the resource that is allocated to the at least one basicpattern in the physical layer transmission unit are described above withreference to the method 300, and therefore are not described hereinagain.

The method 500 for obtaining a reference signal shown in FIG. 5 is areceive side method corresponding to the method 300 for sending areference signal shown in FIG. 3, and technical features related to themethod 500 are described above in detail with reference to accompanyingdrawings, for example but not limited to FIG. 3 and FIG. 4, andtherefore are not described herein again.

FIG. 6 is a schematic diagram of a logical structure of an apparatus 600for sending a reference signal according to an embodiment of the presentdisclosure. In a specific implementation process, the apparatus 600 maybe a transmit end device. The transmit end device may be, for examplebut not limited to, the base stations 202 to 206 or the terminal devices208 to 222 in FIG. 2. As shown in FIG. 6, the apparatus 600 includes adetermining module 602 and a sending module 604.

The determining module 602 is configured to determine, based on aresource that is allocated to the reference signal in a basic patterncorresponding to a reference signal and a resource that is allocated toat least one basic pattern in a physical layer transmission unit, aresource to be occupied by the reference signal in the physical layertransmission unit.

The sending module 604 is configured to send the reference signalthrough the determined resource.

The basic pattern may occupy at least one OFDM symbol in time domain,and may occupy at least one subcarrier in frequency domain. In addition,in the basic pattern, the reference signal may occupy at least one OFDMsymbol in time domain, and may occupy at least one subcarrier infrequency domain. In other words, the resource that is allocated to thereference signal in the basic pattern corresponding to the referencesignal may include at least one OFDM symbol in time domain, and mayinclude at least one subcarrier in frequency domain. More specifically,the at least one OFDM symbol occupied by the reference signal in thebasic pattern in time domain may be a plurality of consecutive OFDMsymbols.

The reference signal is used for at least one of the followingobjectives:

determining channel state information;

performing beam management; and

demodulating a received signal.

In a specific implementation process, the transmit end device sends thereference signal to a receive end device through the determinedresource. To enable the receive end device to learn the resource that isallocated to the at least one basic pattern in the physical layertransmission unit, the transmit end device may also notify the receiveend device of the resource that is allocated to the at least one basicpattern in the physical layer transmission unit. In a specificimplementation process, such an operation may be performed by thesending module 604. Related technical details that the transmit enddevice notifies the receive end device of the resource that is allocatedto the at least one basic pattern in the physical layer transmissionunit are described above with reference to the method 300, and thereforeare not described herein again.

The apparatus 600 is configured to perform the method 300 shown in FIG.3. Technical features related to the apparatus 600 are described abovein detail with reference to accompanying drawings, for example but notlimited to FIG. 3 and FIG. 4, and therefore are not described hereinagain.

FIG. 7 is a schematic diagram of a logical structure of an apparatus 700for obtaining a reference signal according to an embodiment of thepresent disclosure. In a specific implementation process, the apparatus700 may be a receive end device. The receive end device may be, forexample but not limited to, the terminal devices 208 to 222 or the basestations 202 to 206 in FIG. 2. As shown in FIG. 7, the apparatus 700includes a determining module 702 and an obtaining module 704.

The determining module 702 is configured to determine, based on aresource that is allocated to the reference signal in a basic patterncorresponding to a reference signal and a resource that is allocated toat least one basic pattern in a physical layer transmission unit, aresource occupied by the reference signal in the physical layertransmission unit.

The obtaining module 704 is configured to obtain the reference signalthrough the determined resource.

The basic pattern may occupy at least one OFDM symbol in time domain,and may occupy at least one subcarrier in frequency domain. In addition,in the basic pattern, the reference signal may occupy at least one OFDMsymbol in time domain, and may occupy at least one subcarrier infrequency domain. In other words, the resource that is allocated to thereference signal in the basic pattern corresponding to the referencesignal may include at least one OFDM symbol in time domain, and mayinclude at least one subcarrier in frequency domain. More specifically,the at least one OFDM symbol occupied by the reference signal in thebasic pattern in time domain may be a plurality of consecutive OFDMsymbols.

The reference signal is used for at least one of the followingobjectives:

determining channel state information;

performing beam management; and

demodulating a received signal.

In a specific implementation process, a transmit end device sends thereference signal to the receive end device by using the determinedresource. To enable the receive end device to learn the resource that isallocated to the at least one basic pattern in the physical layertransmission unit, the transmit end device may also notify the receiveend device of the resource that is allocated to the at least one basicpattern in the physical layer transmission unit. In a specificimplementation process, the determining module 702 may obtain theresource that is allocated to the at least one basic pattern in thephysical layer transmission unit. Alternatively, a receiving module (notshown) may obtain the resource that is allocated to the at least onebasic pattern in the physical layer transmission unit. Related technicaldetails that the transmit end device notifies the receive end device ofthe resource that is allocated to the at least one basic pattern in thephysical layer transmission unit are described above with reference tothe method 300, and therefore are not described herein again.

The apparatus 700 is a receive side apparatus corresponding to theapparatus 600, and is configured to perform the method 500 shown in FIG.5. Technical features related to the apparatus 700 are described abovein detail with reference to accompanying drawings, for example but notlimited to FIG. 3 and FIG. 4, and therefore are not described hereinagain.

FIG. 8 is a schematic diagram of a hardware structure of an apparatus800 for sending a reference signal according to an embodiment of thepresent disclosure. As shown in FIG. 8, the apparatus 800 includes aprocessor 802, a transceiver 804, a plurality of antennas 806, a memory808, an I/O (input/output, Input/Output) interface 810, and a bus 812.The transceiver 804 further includes a transmitter 8042 and a receiver8044. The memory 808 is further configured to store an instruction 8082and data 8084. In addition, the processor 802, the transceiver 804, thememory 808, and the I/O interface 810 are in communication connectionwith each other by using the bus 812, and the plurality of antennas 806are connected to the transceiver 804.

The processor 802 may be a general purpose processor, for example butnot limited to, a central processing unit (Central Processing Unit,CPU), or may be a special purpose processor, for example but not limitedto, a digital signal processor (Digital Signal Processor, DSP), anapplication-specific integrated circuit (Application-Specific IntegratedCircuit, ASIC), or a field programmable gate array (Field ProgrammableGate Array, FPGA). In addition, the processor 802 may alternatively be acombination of a plurality of processors. Particularly, in the technicalsolution provided in this embodiment of the present disclosure, theprocessor 802 may be configured to perform, for example, step 302 in themethod 300 for sending a reference signal shown in FIG. 3, and anoperation performed by the determining module 602 in the apparatus 600for sending a reference signal shown in FIG. 6. The processor 802 may bea processor specially designed to perform the foregoing step and/oroperation, or may be a processor that performs the foregoing step and/oroperation by reading and executing the instruction 8082 stored in thememory 808. The processor 802 may need to use the data 8084 whenperforming the foregoing step and/or operation.

The transceiver 804 includes the transmitter 8042 and the receiver 8044.The transmitter 8042 is configured to send a signal by using at leastone of the plurality of antennas 806. The receiver 8044 is configured toreceive a signal by using at least one of the plurality of antennas 806.Particularly, in the technical solution provided in this embodiment ofthe present disclosure, the transmitter 8042 may be specificallyconfigured to perform, for example, step 304 and the step of notifyingthe receive end device of the resource that is allocated to the at leastone basic pattern in the physical layer transmission unit in the method300 for sending a reference signal shown in FIG. 3, and an operationperformed by the sending module 604 in the apparatus 600 for sending areference signal shown in FIG. 6, by using at least one of the pluralityof antennas 806.

The memory 808 may be various types of storage media, for example, arandom access memory (RAM), a read-only memory (ROM), a non-volatile RAM(NVRAM), a programmable ROM (PROM), an erasable PROM (EPROM), anelectrically erasable PROM (EEPROM), a flash memory, an optical memory,and a register. The memory 808 is specifically configured to store theinstruction 8082 and the data 8084. The processor 802 may perform theforegoing step and/or operation by reading and executing the instruction8082 stored in the memory 808, and may need to use the data 8084 whenperforming the foregoing step and/or operation.

The I/O interface 810 is configured to receive an instruction and/ordata from a peripheral device, and output an instruction and/or data tothe peripheral device.

It should be noted that, in a specific implementation process, theapparatus 800 may further include other hardware devices, which are notenumerated in this specification.

FIG. 9 is a schematic diagram of a hardware structure of an apparatus900 for obtaining a reference signal according to an embodiment of thepresent disclosure. As shown in FIG. 9, the apparatus 900 includes aprocessor 902, a transceiver 904, a plurality of antennas 906, a memory908, an I/O (Input/Output) interface 910, and a bus 912. The transceiver904 further includes a transmitter 9042 and a receiver 9044. The memory908 is further configured to store an instruction 9082 and data 9084. Inaddition, the processor 902, the transceiver 904, the memory 908, andthe I/O interface 910 are in communication connection with each other byusing the bus 912, and the plurality of antennas 906 are connected tothe transceiver 904.

The processor 902 may be a general purpose processor, for example butnot limited to, a central processing unit (CPU), or may be a specialpurpose processor, for example but not limited to, a digital signalprocessor (DSP), an application-specific integrated circuit (ASIC), or afield programmable gate array (FPGA). In addition, the processor 902 mayalternatively be a combination of a plurality of processors.Particularly, in the technical solution provided in this embodiment ofthis application, the processor 902 is configured to perform, forexample, step 502, step 504, and the step of obtaining the resource thatis allocated to the at least one basic pattern in the physical layertransmission unit in the method 500 for obtaining a reference signalshown in FIG. 5, and operations performed by the determining module 702and the obtaining module 704 in the apparatus 700 for obtaining areference signal shown in FIG. 7. The processor 902 may be a processorspecially designed to perform the foregoing step and/or operation, ormay be a processor that performs the foregoing step and/or operation byreading and executing the instruction 9082 stored in the memory 908. Theprocessor 902 may need to use the data 9084 when performing theforegoing step and/or operation.

The transceiver 904 includes the transmitter 9042 and the receiver 9044.The transmitter 9042 is configured to send a signal by using at leastone of the plurality of antennas 906. The receiver 9044 is configured toreceive a signal by using at least one of the plurality of antennas 906.Particularly, in the technical solution provided in this embodiment ofthe present disclosure, the receiver 9044 may be configured to performan operation performed by the receiving module in the apparatus 700shown in FIG. 7.

The memory 908 may be various types of storage media, for example, arandom access memory (RAM), a read-only memory (ROM), a non-volatile RAM(NVRAM), a programmable ROM (PROM), an erasable PROM (EPROM), anelectrically erasable PROM (EEPROM), a flash memory, an optical memory,and a register. The memory 908 is specifically configured to store theinstruction 9082 and the data 9084. The processor 902 may perform theforegoing step and/or operation by reading and executing the instruction9082 stored in the memory 908, and may need to use the data 9084 whenperforming the foregoing step and/or operation.

The I/O interface 910 is configured to receive an instruction and/ordata from a peripheral device, and output an instruction and/or data tothe peripheral device.

It should be noted that, in a specific implementation process, theapparatus 900 may further include other hardware devices, which are notenumerated in this specification.

The foregoing descriptions are merely examples of embodiments of thepresent disclosure, and are not intended to limit the scope of thepresent disclosure. Any modification, equivalent replacement, orimprovement made without departing from the spirit and principle of thepresent disclosure should fall within the protection scope of thepresent disclosure. For example, when the technical solutions providedin the embodiments of the present disclosure are applied to a particularscenario or a particular condition, all other processing steps addedbefore, during, and/or after steps of the methods provided in theembodiments of the present disclosure and other processing modules addedto the apparatuses provided in the embodiments of the present disclosureto complete additional processing should be considered as furtherimprovements made based on the technical solutions provided in theembodiments of the present disclosure, and therefore fall within thescope of the present disclosure.

It should be understood that sequence numbers of the foregoing processesdo not mean particular execution sequences in the embodiments of thepresent disclosure. The execution sequences of the processes should bedetermined based on functions and internal logic of the processes, andshould not be construed as any limitation on the implementationprocesses of the embodiments of the present disclosure.

A person of ordinary skill in the art may be aware that, in combinationwith the examples described in the embodiments disclosed in thisspecification, units and algorithm steps may be implemented byelectronic hardware or a combination of computer software and electronichardware. Whether the functions are performed by hardware or softwaredepends on particular applications and design constraint conditions ofthe technical solutions. A person skilled in the art may use differentmethods to implement the described functions for each particularapplication, but it should not be considered that the implementationgoes beyond the scope of the present disclosure.

It may be clearly understood by a person skilled in the art that, forconvenient and brief description, for a detailed working process of theforegoing system, apparatus, and unit, refer to a corresponding processin the foregoing method embodiments, and details are not describedherein again.

In the embodiments provided in this application, it should be understoodthat the disclosed system, apparatus, and method may be implemented inother manners. For example, the described apparatus embodiment is merelyan example. For example, the unit division is merely logical functiondivision and may be other division in actual implementation. Forexample, a plurality of units or components may be combined orintegrated into another system, or some features may be ignored or notperformed. In addition, the displayed or discussed mutual couplings ordirect couplings or communication connections may be implemented byusing some interfaces. The indirect couplings or communicationconnections between the apparatuses or units may be implemented inelectronic, mechanical, or other forms.

The units described as separate parts may or may not be physicallyseparate, and parts displayed as units may or may not be physical units,may be located in one position, or may be distributed on a plurality ofnetwork units. Some or all of the units may be selected based on actualrequirements to achieve the objectives of the solutions of theembodiments.

In addition, function units in the embodiments of the present disclosuremay be integrated into one processing unit, or each of the units mayexist alone physically, or two or more units are integrated into oneunit.

When the functions are implemented in a form of a software function unitand sold or used as an independent product, the functions may be storedin a computer-readable storage medium. Based on such an understanding,the technical solutions of the present disclosure essentially, or thepart contributing to the prior art, or some of the technical solutionsmay be implemented in a form of a software product. The computersoftware product is stored in a storage medium, and includes severalinstructions for instructing a computer device (which may be a personalcomputer, a server, a network device, or the like) to perform all orsome of the steps of the methods described in the embodiments of thepresent disclosure. The foregoing storage medium includes: any mediumthat can store program code, such as a USB flash drive, a removable harddisk, a read-only memory (ROM), a random access memory (RAM), a magneticdisk, or an optical disc.

The foregoing descriptions are merely specific implementations of thepresent disclosure, and are not intended to limit the protection scopeof the present disclosure. Any variation or replacement readily figuredout by a person skilled in the art within the technical scope disclosedin the present disclosure shall fall within the protection scope of thepresent disclosure. Therefore, the protection scope of the presentdisclosure shall be subject to the protection scope of the claims.

What is claimed is:
 1. A method for obtaining a reference signal,comprising: determining, based on a first resource that is allocated toa reference signal in a basic pattern corresponding to the referencesignal and a second resource that is allocated to at least one basicpattern in a physical layer transmission unit, a third resource occupiedby the reference signal in the physical layer transmission unit, whereinthe physical layer transmission unit comprises the at least one basicpattern and a plurality of resources that are not occupied by the atleast one basic pattern; sending the reference signal through the thirdresource; and sending information indicating the resource is allocatedto the at least one basic pattern in the physical layer transmissionunit, wherein the basic pattern occupies a plurality of consecutiveOrthogonal Frequency Division Multiplexing (OFDM) symbols in a timedomain, and the basic pattern occupies a plurality of consecutivesubcarriers in a frequency domain.
 2. The method according to claim 1,wherein, in the basic pattern, the reference signal occupies at leastone OFDM symbol in a time domain and at least one subcarrier in afrequency domain.
 3. The method according to claim 2, wherein the atleast one OFDM symbol occupied by the reference signal in the basicpattern in the time domain is a plurality of consecutive OFDM symbols.4. The method according to claim 1, wherein the reference signal is usedfor one or more of: determining channel state information; performingbeam management; or demodulating a received signal.
 5. The methodaccording to claim 1, wherein the information indicating the resource isallocated to the at least one basic pattern in the physical layertransmission unit is transmitted through radio resource control (RRC)signaling.
 6. An apparatus for obtaining a reference signal, comprising:a transceiver; at least one processor; and one or more memories coupledto the at least one processor and storing programming instructions forexecution by the at least one processor to cause the apparatus to:determine, based on a first resource that is allocated to a referencesignal in a basic pattern corresponding to the reference signal and asecond resource that is allocated to at least one basic pattern in aphysical layer transmission unit, a third resource occupied by thereference signal in the physical layer transmission unit, wherein thephysical layer transmission unit comprises the at least one basicpattern and a plurality of resources that are not occupied by the atleast one basic pattern; send the reference signal through the thirdresource; and send information indicating the resource is allocated tothe at least one basic pattern in the physical layer transmission unit,wherein the basic pattern occupies a plurality of consecutive OrthogonalFrequency Division Multiplexing (OFDM) symbols in a time domain, and thebasic pattern occupies a plurality of consecutive subcarriers in afrequency domain.
 7. The apparatus according to claim 6, wherein, in thebasic pattern, the reference signal occupies at least one OFDM symbol ina time domain and occupies at least one subcarrier in a frequencydomain.
 8. The apparatus according to claim 7, wherein the at least oneOFDM symbol occupied by the reference signal in the basic pattern in thetime domain is a plurality of consecutive OFDM symbols.
 9. The apparatusaccording to claim 6, wherein the reference signal is used for one ormore of: determining channel state information; performing beammanagement; or demodulating a received signal.
 10. The apparatusaccording to claim 6, wherein the information indicating the resource isallocated to the at least one basic pattern in the physical layertransmission unit is transmitted through radio resource control (RRC)signaling.
 11. A non-transitory computer-readable storage medium,wherein the computer-readable storage medium stores computer programinstructions, and when the computer program instructions run on acomputer, the computer is configured to perform a method comprising:determining, based on a first resource that is allocated to a referencesignal in a basic pattern corresponding to the reference signal and asecond resource that is allocated to at least one basic pattern in aphysical layer transmission unit, a third resource occupied by thereference signal in the physical layer transmission unit, wherein thephysical layer transmission unit comprises the at least one basicpattern and a plurality of resources that are not occupied by the atleast one basic pattern; sending, the reference signal through the thirdresource; and sending information indicating the resource is allocatedto the at least one basic pattern in the physical layer transmissionunit, wherein the basic pattern occupies a plurality of consecutiveOrthogonal Frequency Division Multiplexing (OFDM) symbols in a timedomain, and the basic pattern occupies a plurality of consecutivesubcarriers in a frequency domain.
 12. The non-transitory computerstorage medium according to claim 11, wherein, in the basic pattern, thereference signal occupies at least one OFDM symbol in a time domain andoccupies at least one subcarrier in a frequency domain.
 13. Thenon-transitory computer storage medium according to claim 12, whereinthe at least one OFDM symbol occupied by the reference signal in thebasic pattern in the time domain is a plurality of consecutive OFDMsymbols.
 14. The non-transitory computer storage medium according toclaim 11, wherein the reference signal is used for one or more of:determining channel state information; performing beam management; ordemodulating a received signal.
 15. The non-transitory computer storagemedium according to claim 11, wherein the information indicating theresource is allocated to the at least one basic pattern in the physicallayer transmission unit is transmitted through radio resource control(RRC) signaling.